i am experiencing a whistle at idle. it seems to come and go very randomly. some days it will happen once the RPM drops below 1000, other days, only at 650. ive tried various conditions (ie. AC on, heater on, blower on) and sometimes its always there, sometimes not. another problem is that my idle is also random and rough. last night i was driving, and sometimes it would idle at 650, other times, 950, 850, 600, 500. it jumps all over the place, but never above 950. when every it idles below 650 my car gets this very noticable vibration.

the whistle is comming form the left side of the engine bay where the pullies and belts are. the belts are fine, they were replaced about 15k ago. the alternator is also fine. someone suggested maybe a vacuum leak, which may explain the idle problems as well, but someone else also said it may be the water pump or AC compressor. how can i check the pump and compressor to see if they are fine? also, if it turns out to be a vacuum leak, how do i find it?

 

Just clean your TB, that'll fix it.

Seriously, it does sound like a vacuum leak. Could be from the intake runners or the manifold. That could explain why your idle jumps around. Another cause of hunting idle speed is a defective TPS. But thats not causing your whistle.

 

i checked my TPS, and it is fine.

the idle is not really hunting. it doesnt jump arround a lot, the idle changes, but its consistant. when ever i stop at a stop sign or red light it will keep going down to say 900, then maybe 20 minutes later ill stop and it will go to maybe 600 for the next 15-20 minutes. i never see it jumping arround, just changes here and there. i guess you can say thats a hunting idle, i always thought that was when you see it moving up and down.

 

vaccum leak for sure

 

k thats what i thought. how do i find the leak? when i open the hood, i cant exactly localize the whistle, i can tell its louder on the left side of the bay, but thats it. is there a seal or hose that commonly break to cause this leak, or is there something i can safely spray in my TB to see where it leaks out?

 

Check all your vacuume lines for cracks or loose connections. Spray WD-40 around all the intake seals while the car is running. When you cover the leak area with oil the whistle will stop. That should pin point the area or seal thats faulty.

 

maybe a bad pulley bearing or something. that would give you a whistle noise and also effect your idle by the belt slipping .

 

Whistle at idle = Stillen Vortech supercharger.

 

hahaha i know, some people pay a lot of money to get that whistle sound.

 

thanks guys, ill check it out.

this sounds nothing like an s/c, more like ****in whistle tips, itgs driving me crazy.